Carbon

Radiocarbon dating (sometimes simply known as carbon dating) is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 (C) to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" (BP), "Present" being defined as 1950. Such raw ages can be calibrated to give calendar dates. One of the most frequent uses of radiocarbon dating is to estimate the age of organic remains from archaeological sites. When plants fix atmospheric carbon dioxide (CO2) into organic material during photosynthesis they incorporate a quantity of C that approximately matches the level of this isotope in the atmosphere (a small difference occurs because of isotope fractionation, but this is corrected after laboratory analysis). After plants die or they are consumed by other organisms (for example, by humans or other animals) the C fraction of this organic material declines at a fixed exponential rate due to the radioactive decay of C. Comparing the remaining C fraction of a sample to that expected from atmospheric C allows the age of the sample to be

Binghamton University researchers have demonstrated an eco-friendly process that enables unprecedented spatial control over the electrical properties of graphene oxide. This two-dimensional nanomaterial has the potential ...

Rice University researchers discovered that putting nanotube pillars between sheets of graphene could create hybrid structures with a unique balance of strength, toughness and ductility throughout all three dimensions.

Carbon fibers are stronger and lighter than steel, and composite materials based on carbon-fiber-reinforced polymers are being used in an expanding range of aerospace, automotive, and other applications – including major ...

An international team of researchers has examined the optical and dielectric properties of thin macroscopic films based on single-walled carbon nanotubes and obtained an explanation for the metallic nature of their conductivity ...

Ben-Gurion University of the Negev (BGU) and University of Western Australia researchers have developed a new process to develop few-layer graphene for use in energy storage and other material applications that is faster, ...

Using a technique that introduces tiny wrinkles into sheets of graphene, researchers from Brown University have developed new textured surfaces for culturing cells in the lab that better mimic the complex surroundings in ...

Carbon nanotubes (CNTs) are microscopic tubular structures that engineers "grow" through a process conducted in a high-temperature furnace. The forces that create the CNT structures known as "forests" often are unpredictable ...

A new method for producing conductive cotton fabrics using graphene-based inks opens up new possibilities for flexible and wearable electronics, without the use of expensive and toxic processing steps.

In the quest for more efficient vehicles, engineers are using harder and lower-density carbon materials, such as carbon fibers, which can be manufactured sustainably by "baking" naturally occurring soft hydrocarbons in the ...

Developing novel materials from the atoms up goes faster when some of the trial and error is eliminated. A new Rice University and Montreal Polytechnic study aims to do that for graphene and boron nitride hybrids.